The product of a group of scholars who have been working on new directions in Historical Linguistics, this book is focused on questions of grammatical change, and the central issue of grammaticalization in Indo-European languages. Several studies examine particular problems in specific languages, but often with implications for the IE phylum as a whole. Given the historical scope of the data (over a period of four millennia) long range grammatical changes such as the development of gender differences, strategies of definiteness, the prepositional phrase, or of the syntax of the verbal diathesis and aspect, are also treated. The shifting relevance of morphology to syntax, and syntax to morphology, a central motif of this research, has provoked lively debate in the discipline of Historical Linguistics.